Genetic Diversity of Croton L. (Euphorbiaceae) in Thailand

Abstract

Genetic diversity of Croton 15 species were investigated. The results revealed that chromosome numbers of Croton are quite unique of 2n=20, except C. hirtus which contains In=16. Chromosome numbers of 9 species are the first recorded. The genus Croton has base number of 8 and 10. Chromosomes of microsporocytes of Croton are very well stained with propionocarmine. Most of them are clearly paired in bivalent of 1.00-6.00 μm at metaphase I cells of 26.67-63.33 μm (Ø). Chromosomes are balanced disjunction at anaphase I. The results show that Croton are very good fertile and stable in natural habitat and it has a small genome which could be manipulated or improved simply. C. hirtus is probably more advanced than the others.